Following should work with boot-fx's presenter:

@Model(className = "MainCntrl", targetId = "", properties = {
    @Property(name = "value", type = String.class)
})
public class Main {
    public static void main(String... args) throws IOException {
        BrowserBuilder bb = BrowserBuilder.newBrowser().loadPage("page1.html").loadFinished(new Runnable() {
            @Override
            public void run() {
                new MainCntrl("first page").applyBindings();
            }
        });
        showAsync(bb);

        BrowserBuilder b2 = BrowserBuilder.newBrowser().loadPage("page2.html").loadFinished(new Runnable() {
            @Override
            public void run() {
                new MainCntrl("2nd page").applyBindings();
            }
        });
        showAsync(b2);
    }

    private static void showAsync(BrowserBuilder bb) {
        new Thread("Show async") {
            @Override
            public void run() {
                bb.showAndWait();
            }

        }.start();
    }
}


currently it does not work.